1. Field of the Invention
The present invention relates to an exhaust turbo-charger for use in an internal combustion engine. The present invention also pertains to a radial flow gas turbine which has the same structure as that of an exhaust turbo-charger.
2. Prior Art
FIG. 8 shows the structure of a conventional variable capacity radial flow turbine. A turbine housing 31 of the radial flow turbine has therein a turbine wheel 32, and defines a passageway 35 for a working gas such as exhaust gas. A vane 33 is provided in a working gas intake 36 of the passageway 35 through which the gas flows into the turbine wheel 32. The turbine flow rate is varied by opening and closing the vane 33.
FIG. 9 shows a turbine housing 31 of another variable capacity radial flow turbine which is not equipped with a capacity varying mechanism and which has an exhaust passageway 35 divided into two chambers by a partition 20.
When a variable capacity radial flow turbine of the type shown in FIG. 8 is used with a multicylinder engine, the effect of pulsations in the exhaust is reduced. This reduction in the effect of pulsations has therefore made it difficult to obtain a high charging pressure when the rotational speed of the engine is low.
With a turbine having a turbine housing with a partition such as that shown in FIG. 9, the pulsations in the exhaust can be effectively utilized. However, it does not have any capacity varying mechanism, resulting in a narrowing of the suitable matching range.